The invention, relates to a machine housing with a split bearing arrangement, particularly a journal bearing in piston machines, with a bearing cover clampably arranged on a bearing block, with the two being connected with one another with respect to their clamping faces at least in partial areas via corresponding profiles in a form-fit connection.
For the exactly positioned assignment of bearing cover and bearing block, it is known in the art to fix the bearing cover in relation to the bearing block by means of alignment pins, alignment sleeves, or alignment collars on the bearing cover screws. For high transverse loads, the bearing cover may in addition be fit tightly within the machine housing or on the bearing block. To absorb high transverse loads, it is furthermore known to provide the two clamping faces of bearing block and bearing cover with corresponding tooth profiles, as proposed, for example, in generic German utility model DE-U 68 12 460.
Such profiles have the drawback of being costly due to their production by chip-removing machining.
Furthermore, FR-A 1 162 407 proposes, for the cost-effective production of the clamping faces of two parts that are connected by means of screws and are to be positioned with high precision, to produce the clamping faces by electrical discharge machining with one of the parts serving as tool electrode. This known process produces corresponding rough surfaces.
The object of the invention is to define a procedure for a more advantageous forming of a profile for a generic machine housing using electrical discharge machining.
The invention advantageously makes it possible to perfectly shape an exact form-fit profile in bearing block and bearing cover, in similar as well as in dissimilar materials, particularly in a bearing cover made of an iron material. Cutting edge-like projections or pyramid-type points above triangular or rectangular bases produced by chip removing machining serve as generating profiles.
Another further development of the invention discloses by means of electrical discharge machining, a tool electrode having a profile of the clamping face which is used to form a corresponding profile in the clamping face of the bearing block of the machine housing, which serves as the workpiece electrode, such that by means of electrical discharge machining an eroded rough surface with a roughness Ra of approx. 50 xcexcm-300 xcexcm is produced in associated clamping faces of bearing cover and bearing block, each made of an aluminum alloy and spaced at a distance from the other corresponding to the machining process, with a fracture surface-like tooth profile being achieved by means of hard freestanding inclusions in the clamping faces of bearing block and bearing cover, which form corresponding indentations in the respective opposite face.
DE 43 32 444 A1 discloses a bearing arrangement split by fracture separation with a molded body formed from a ceramic material in a light metal cast alloy, wherein the molded body, to achieve fracture surfaces with a distinct mutually meshing form when reassembled, additionally contains freestanding ceramic particles. The use of these particles as xe2x80x9cauxiliary electrodesxe2x80x9d not only advantageously accelerates the machining process, but also achieves a better form closure of the two clamping faces.
The above-described further development of the invention makes it possible to achieve a fracture surface-like tooth profile in the clamping faces without the high loads required in fracture separation that cause a disadvantageous deformation of the respective workpiece.
This advantageous further development is used, in particular, for a crankshaft bearing frame of a V-engine, wherein the machine housing and the bearing frame are each made of an aluminum alloy.